HIV Combination Drug Looks Promising

The results from an ongoing clinical trial of the drug Trizivir (abacavir + AZT [Retrovir; zidovudine] + 3TC [Epivir; lamivudine]), the first tablet to combine 3 HIV medications, were presented at the recent Interscience Conference on Antimicrobial Agents and Chemotherapy to demonstrate the drug's versatility in treating HIV. Trizivir is a fixed-dose combination tablet containing 3 nucleoside reverse transcriptase inhibitors (NRTIs) and is the only HIV drug in the United States to do so. In an open-label study, 114 treatment-naive patients were randomized to receive a regimen of either Trizivir plus tenofovir disoproxil fumarate or a regimen of 2 NRTIs, Combivir (AZT + 3TC) and efavirenz, a nonnucleoside reverse transcriptase inhibitor (NNRTI). At week 48 of the intent-to-treat analysis, 70% of the patients on the Trizivir regimen and 68% of the patients on the Combivir regimen had undetectable viral load.

In a second study presented at the same conference, 51 patients had poor results involving early virologic failure while on a regimen of Retrovir or stavudine plus Epivir. Allan Rodriguez, MD, with the division of infectious diseases at the University of Miami School of Medicine, concluded, "Patients with early virologic failure on an NNRTI-based or PI [protease inhibitor]-based regimen may be appropriate candidates for a quad regimen containing Trizivir." In fact, Trizivir is indicated only for patients requiring the 3 components of the drug.